Point Charges creating an electric field

A point charge q =-4.00 nC is at the point x = 0.600 m, y = 0.800 m, and a second point charge q=6nC is at the point x = 0.600 m, y = 0.

A)Calculate the magnitude of the net electric field at the origin due to these two point charges.

I assume i can just treat the electric field charge as a vector pointed towards the - charge from the origion, using E = (1/4*pi*E_0)(q/r^2).
The other charge is therefore a horizontal vector on the x axis pointing inwards.
After adding components together, I came to:
(8.988*10^9)(16.97108653*10^-9), any idea where I went wrong?

Next.
B)What is the direction of the net electric field at the origin due to these two point charges.
I assume I would just use the same technique here, and ended up with 169.1314747 degrees up from the x-axis... any ideas on where i'm messing up?